Do they ever forget?

Have you ever made a mistake? When you apologized over and over did the person say they forgave you? Did they really or do they still bring it up? This may be something that you are experiencing. It happened to me. I made a huge mistake once and every once in a while my husband will make a smart or sarcastic comment. I know exactly what he is referening. It makes me very upset. It even hurts me. I think that we have moved past that thing and everytime he does that it just pulls me right back to that place of being apologetic about something that happened so long ago. Why do we do that to each other? Why cant people just forgive and let it alone? Have you ever had anything like this happen to you? Or are you the one that keeps bringing something from the past up?